How to Kill Creeping Bentgrass (Weedy Invasions) in Perennial Ryegrass Without Hurting Your Lawn
Direct Agronomic Answer
To selectively kill Creeping Bentgrass (Weedy Invasions) in Perennial Ryegrass without damaging your turf, apply Tenacity (Mesotrione 40%) when air temperatures are between 55°F and 85°F.
Mesotrione selectively bleaches out Bentgrass while leaving desired cool-season turf unharmed. Tenacity can even be used at seeding when overseeding with turf-type tall fescue.
1. Labeled Safe Herbicides That Kill Creeping Bentgrass (Weedy Invasions) in Perennial Ryegrass
| Recommended Product | Active Ingredient & Group | Application Temp (°F) | Surfactant & Mixing Protocol | Where to Buy |
|---|---|---|---|---|
| Tenacity EPA Reg. 100-1267 |
Mesotrione 40% Group 27 (HPPD Inhibitor) |
55°F – 85°F Rainfast: 6h |
Always apply with Non-Ionic Surfactant (NIS) at 1 tsp (5 mL) per gallon of water for post-emergent applications. Causes temporary white bleaching on susceptible weeds and turf tips. | Check Price at DoMyOwn View on Amazon |
3. Optimal Seasonal Timing & Temperature Thresholds
Begin applications in late August to early September so overseeding of desirable grass seed can occur immediately following treatment.
Fall treatments allow optimal cool-season turf recovery in the bare patches left behind by decaying bentgrass mats.
4. Diagnostic Checklist: Confirm It Is Creeping Bentgrass (Weedy Invasions) Before Spraying
- Very fine, soft, blue-green puffy patches that lie flat under mowing
- Extensive surface stolons creating a thatch-heavy spongy carpet
- Distinct tall membranous ligule with rounded to pointed tip
Not 100% sure? Use our AI Photo Weed Scanner or review the full Creeping Bentgrass (Weedy Invasions) Botanical Profile.